This invention relates to pipe arching apparatus, and more particularly to a pipe arching apparatus that flattens and elongates the lower circumference of a pipe positioned directly upon the ground.
Arched pipe is used for highway drainage systems and various other construction projects where diversion of water flow or drainage of runoff is required. Full round pipe is suitable for most applications. However, sometimes it is beneficial to use a round pipe that has been forcibly widened at the bottom to increase the water flow area.
Prior pipe arches have been formed in the factory, either by an external pipe arching apparatus or by an internal pipe arching apparatus. To affect external pipe arching, force is applied directly to the external surface of the pipe to compress it until a desired shape is obtained. Although pipe arched by an external pipe arching apparatus is suitable for some applications, the act of forcibly reshaping the outer circumference could structurally weaken the pipe. A more uniform arch can be obtained by using an internal pipe arching apparatus.
A typical internal pipe arching apparatus utilizes a horizontal beam, with longitudinally extending radius forms mounted on opposite sides of the beam. The beam is about 25 feet long. The radius forms are extendible in opposite directions in a horizontal plane to forcibly reform the internal side walls of a pipe section that is suspended on the beam. As the side walls of the pipe are stretched to flatten the bottom of the pipe, some stretching and flattening of the upper pipe circumference also occurs which could structurally weaken the pipe.
A recent attempt was made to produce a pipe arching apparatus that could be used at the job site. The apparatus featured the typical horizontal beam arrangement, with a forklift truck at one end and a wheel support arrangement at the other. This apparatus could not be readily transported to the job site due to size and weight considerations. Additionally, it could not be self propelled to the job site unless the job site was within a very short distance. Even if it were practical to get this apparatus to the job site, it would only be able to arch a pipe of a size it could lift into arching position.